A couple accused of leaving their severely injured two-year-old daughter at a hospital and keeping their other adopted children in putrid conditions have been arrested after a five-year manhunt.

The search for Janet and Ramon Barreto began when they skipped bail in 2009 on manslaughter and child abuse charges. They were arrested yesterday after a tip led authorities to a shopping mall in Portland, Oregon.

The couple left two-year-old Ena Barreto at a northern Mississippi hospital in 2008, telling the medical staff she had fallen from a shopping cart, authorities said. The girl died after she was taken to a children's hospital in Memphis, Tennessee.

The Barretos were jailed in Portland and awaiting extradition to Mississippi.

The Barretos' daughter Marainna Torres was convicted in Ena's death in 2010. At her trial, she said she feared her parents and they forced her to punish the children, who were mostly under the age of 3, the Northeast Mississippi Daily Journal reported at the time. Torres said she threw the girl across the room and she hit her head.

Authorities say the Barretos had adopted at least seven children from Guatemala beginning in 2005, and kept them inside an atrocious-smelling mobile home in New Albany in northern Mississippi. The children were sometimes bound with duct tape and fed mostly cereal and bologna, authorities said.

"The crimes they are alleged to have committed are nothing short of horrendous and despicable, and now it is time to let justice be served," said Union County Sheriff Jimmy Edwards.

While living in New Albany, the couple made money selling dogs they raised behind the mobile home, keeping hundreds of sick and injured animals in faeces-filled cages, authorities said.

In 2009, while the couple faced the charges, they were free on $450,000 bond when they slipped away.

The US Marshals Service said it tracked them to a town in Mexico where Ramon Barreto's family lives but lost their trail. The pair was later seen in southern California; including a Huntington Park rental unit they left in June 2012 when their dog sales became a nuisance. Officials said they made money on the run by selling dogs, as well as DVDs and CDs from their van. Ramon also panhandled.

US Marshal Dennis Erby said an infant that was with them when they were arrested had been placed with child protective services. He was unaware if the couple had any other children with them. The adopted children that were with the Barretos in Mississippi were taken into state custody when they were charged five years ago.